www.megadrum.info

First off, great project! I've been planning to do a MIDI drum interface for quite a while, was just about to start rolling my own, but this looks pretty promising! As a pair of fresh eyes, I'd like to pose a couple of questions I'm sure you'll hear more of soon:

- How does one operate this machine? I saw the four SPST pushbutton switches on the digital board, can you please elaborate on the functions of these?
- (May be related to previous question) How does one save the pad configurations as you stated?
- On the analog board, are those all 1/4" jacks? I personally wouldn't want to run 1/4" path cables to every one of the pads from the control module :S
- Do you have any un-compiled source code for the firmware? Curious people like me really want to see how you (or the code's creator) achieved this MIDI system!
- If you do have a PCB, can you please post it? It would help considerably :)
- What are the differences between the ATmega32 and ATmega8 boards functionality-wise? More/less inputs? Faster/slower processing time?

There may be more, but these came into my head from page jumping just now. Thanks for posting this project, I can't wait to learn more and build one!

1. The configuration and settings can be changed either manually using 4 keys (lef, right, up, down) or from a computer through MIDI Sysex. The details of the both of thiese options I'll publish on my return from the holiday. At the moment I can say that manual configuration is made via "LCD menu" and in most cases is self explanatory.
2. Same here. The configuration can be saved in internal eeprom manually via menu or the "save configuration" can be requested using MIDI Sysex. Details later.
3. Essentially it's up to you to decide what jacks to use, just bear in mind not to exceed sensible (reasonable) cable lengths.
4. I have not made up my mind on this. I may, I may not.
5. At present the difference is the number of channel: 22 for Atmega32, 20 for Atmega8.
number of input gain levels: 9 for Atmega32, 3 fro Atmega8
number of saved configs/saved drum maps: 4/15 for Atmega32, 2/7 for Atmega8
flash memory used: Atmega32 still have a lot of memory available for future extensions. Atmega8 has almost all memory used. Still Atmega8 based MegaDrum is more advanced and more powerful in comparison to other similiar modules.

Sorry for delays with replies, I'm on my holiday right now (see 'News' section).
Thank you for your interest!

Hey dmitri, I hope you had a good holiday! I dove a little deeper into the schematics and was curious about a couple more things I was hoping you could clear up for me

1) Are there any advantages/disadvantages to using either the FT232 or AVR-CDC options (i.e., is one faster than the other, etc?)?
2) What are the functions of the Aux 1 and Aux 2 pads? Programmable to anything we want?
3) Probably a really stupid question, but just to be sure, is the "Pedal" pad to open/close the HiHat?
4) The main website mentioned that this thing could handle up to around 20 input pads, but I count 12 pads in the Analog schematic. There is space on the ATMega32 in the Digital Board schematic for 6 more inputs in the P port, but are they supported by the firmware you have written?

I hope you post pictures of your analog board/pads, sounds really neat! Thanks for the information!

1) AVR-CDC is easier to build since Atmega8 is in DIP packaging. The disadvantage is that with Windows CDC drivers only one application at a time can open a COM port. I soldered myself only AVR-CDC. With FT232 instead of soldering it myself I picked up one of those USB->Serial adapters based on FT232, disassembled it, cut unneeded wires and soldered in a connector.
2) You can assign any note to any pad. Aux1 and Aux2 are not exceptions, I just did not know how to name them.
3) That's right, it is a HiHat pedal controller input.
4) If you look at the Analogue Board schematics you will notice that all input sockets, except Kick and HiHat Pedal, are stereo(well, Pedal is also stereo but it's for providing voltage to a pedal controller) . You can split all of them and have 20 mono inputs, you can leave all of them as stereo and have 10 stereo inputs, or you can "mix and match" and have between 10 and 20 inputs, plus, of course, Kick and Pedal inputs. It's up to you to decide how to use them and all those combinations are supported in firmware.

Regards